In some cases, the dielectric constants of objects under investigation, especially living tissue, are very homogeneous, and reliable results which can be presented with a clear contrast cannot always be attained with conventional microwave-based investigations.
Magnetic-resonance tomographies are prepared as an alternative. With the help of contrast media, more accurate results can be obtained. However, the preparation of magnetic-resonance tomographies is associated with high costs. Furthermore, in the case of patients in intensive care, an investigation of this kind is possible only with difficulty.
Accordingly, DE 44 33 572 A1 discloses the use of gadolinium-diethylene-triamino-penta-acetate (Gd-DPTA) as a contrast medium for magnetic-resonance investigations.